1. Field of the Invention
The present invention relates to a plasma processing method and a plasma processing apparatus.
2. Description of the Related Art
In a semiconductor device production process, a variety of film deposition processes is performed on a semiconductor wafer (which is hereafter referred to as a “wafer”) by a deposition method such as atomic layer deposition (ALD).
Research and development of a turntable-type film deposition apparatus for performing ALD have been conducted in these years. The turntable-type film deposition apparatus includes a rotatable turntable disposed in a vacuum chamber. The turntable has concave portions where wafers are placed. Each of the concave portions has a diameter that is slightly greater than a diameter of each of the wafers. Above the turntable, a supply area to which a reaction gas A is supplied, a supply area to which a reaction gas B is supplied, and a separation area for separating the supply areas are defined.
Also, Japanese Laid-Open Patent Application Publication No. 2013-161874, for example, discloses a turntable-type film deposition apparatus including a plasma generator. The disclosed turntable-type film deposition apparatus uses plasma generated by the plasma generator to deposit various films (functional films) on a substrate, modify a film including carbon deposited on a substrate, and etch a film deposited on a substrate.
In addition, in an etching apparatus other than ALD, a CVD (Chemical Vapor Deposition) apparatus and the like, the plasma process is utilized for etching, film deposition, film modification and the like.
However, in the conventional plasma process, there was no direct and effective parameter for controlling a distribution of an amount of plasma processing within a wafer. Accordingly, the method of adjusting the plasma process had to rely on only an indirect method of adjusting parameters in such a way as to change gas species, a flow rate of the gas, or a pressure and the like that do not necessarily indicate a high correlation with the distribution of the amount of plasma processing and then observing the results.